Lamp-socket.



N. MARSHALL.

LAMP SOUKET.

APPLICATION nun OUT. 19, 1909.

989,623. Patented Apr. 18,1911.

a annn'rs-aann'r 1.

555 A I A/VYZVTOH N. MARSH ALL. LAMP SOCKET. APPLIOA'IIIION FILED OUT. 19, 1908. 989,623. Patented Apr. 18, 1911 UNITED STATES PATENT oFFIoE."

NOW MARSHALL, F NEWTON, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGN- MEN'IS, '10 ARROW ELECTRIC COMPANY, OF HARTFORD, CONNECTICUT, ACORIPOBA- TION OF CONNECTICUT.

LAMP-SOCKET.

Specification of Letters Patent.

Patented Apr. 18,1911.

Application filed October 19, 1908. serial No. 458,464.

r i To all whom it may concem:

- The inventionre'lates Be it known that I, Norman MAnsHAflL,

citizen of the United States, residing at Newton, in the county of -Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Lamp-- Sockets; and I do hereby declare the following to be a full, clear, and exact description sockets, and niore especially to that type of sockets in which the current carrying parts are mounted upon a base of porcelain or other insulatin material and are inclosed within a metallic shell and cap.

, The object of the invention is to provide a socket having its various parts constructed and arranged in an improved and simplified manner whereby the current carrying parts are effectively insulated, the number of the parts are reduced, and the manufacture and assembling of the parts facilitated and rendered convenient and inexpensive.

To this end the invention consists in the features of construction and combinations of parts hereinafter described and referred to in the claims, the advantages of which will be apparent to those skilled in the art.

The features of the invention will be readily understood from an inspection of the accompanying drawings, in which- Figure 1 is an elevation of a socket embodying the invention, a part of the shell and cap and of the insulating lining beingbroken away; Fig. 2 is a. vertical central section on line 2-2, Fig. 1; Fig. 3 is a vertical sectional view of the socket base on line 3-3, Fig. 2, a part of the screw shell being omitted; Fig. 4 is a view looking into the screw shell, the screw shell being shown in section,'and the insulating disk within the shell being removed for the sake of clearness; Fig. 5 is a top view of the upper section of the socket base; Fig. 6 is a bottom view of the'same; Fig. 7 is a side elevation looking toward the left in Fig. 5; Fig. 8 is a top view of the lower section of the socket base;'Fig. 9 is a bottom view of the same; Fig. 10 is a side View looking toward the a detail view of the center contact plate; Flg. 13 is an elevation of the socket showing one form of devices for connecting the 'shell and ca of the inclosing casing; Fig. 14 is a vertica sectionalview through the shell and cap on line 14-14, Fig. 15, the'socket base and parts carried thereby being removed; ,Fig.'15 is a sectional view on line 15-'15, Fig. 13, the socket base being shown in plan; Fig. 16 is a perspective view of the u per art of the shell showing the locking proections formedthereon; Fig. 17 is an elevation of a socket cap and shell showing the locking rojections formed in the cap and the locking apertures formed in the shell; Fig. 18 is a vertical-sectional view through the locking device SlltlJWIl in Fig. 17, with the'cap and shell connectedtogether; Fig. 19 is a detail sectional view showing a modified are views showing another form of cap bushing.

As shown in Figs. 1 to 12, the base and .current carrying parts of the socket are inclosed within a metallic casing consisting of the shell 1 and the cap 2, and are separated from the casing by an insulating l ning. 3

fitting within the shell and an insulating lining 4 fitting within the cap.

The porcelain base of the socket comprises an upper section 5 and a lower section 6 which carry and support the current carrying parts of the socket. The socket shown is a key socket, and the upper section 5 of the base is provided in its under face with a recess 7 formed to receive the key frame 8, which is of well known construction, and is secured in the recess 'by a screw 9. The key frame carries the usual contact spring 10 and key shaft 11, upon which is mounted the switch block 12. The end of the key frame adjacent the key 13 is provided with an offset portion 14.- carrying a binding screw, 15

cured. The upper face of the lower section 6 of the base is rece ed to accommodate the .key shaft, and thi section is providedmn one side with a recess 16 in which the end of the key frame carrying the binding the lower section (3 of the base, a recess ,1

switch block 12. lowersection (3 is provided with a recess for receivingand positioning a plate 19 which is provided with anulpward fse't portion 20 which lies wlthln a rec to which one of the conductor wires is sescrew- 15 is located. 011 the opposite side a;-

is formed, the walls of which embrace the. The lower face of th form of cap bushing; and Figs. 20 and 21 50 pierced "for -'t e immedinethe 'side of the'seetion and carries gsbinding'screw' 22. The lower face of the. .fseption '6' is also provided Wlth a recess 23' shaped to receive and hold inpositio'h a center contact plate 24L.

thefbaseare p 26;;and-j2'7 v"which-extend throughholes in and, is'inposition' tor-be engaged by the switch block 'm. This part of the plate 24:

be bent :Io'' asK toform an efi'ective spring contact plate-for cooperating with the switch block,

a: the req ss" 23 inthe face of thee-block 6 being "fji ion3jtn allow fish s I ntor contact andswitch plate is jpositioned bythe recess. 23, and is e d in the' recess by the shell 25 and 'tnterposed'insulating sheet or disk 30. The pla-teiis, practically incl'osed in insulating ma- --the vupward bending of 'terial, a'ndf'is thus efiectually insulated from! the shell 25 and the other'current carrying parts; Since 'the plate lies between the shell and"- thebase; the contact finger 31 may beprvojec'te'd through the insulating sheet and s mto the center of the shell, without requiring Q? ,the cutting away ofa po rtionjof the. wall of shell; A dish-of'mica or other suitable ifiilating mater al is-introdn'ced into the shel l 25, and lies between the center contact and the flan e 'of'the shell, the disk being lasr indicated' in Fig.2. v The plate 19'' which carries the binding screw '22'is normally positioned by the recess 18in the-under face of the block'6, and is held in the recessby the shell at which is forced against the under surface of the plate by the screw 26 and nut 29. The insulating ;disk 30jis provided with an-aperture 35 corresponding. in shape to the shape of the 6i 'f plate 19,- s0-t hat said plateis in engagement and makes electrical connection with the v--- nm.5;- a

' The upper hlock' 5 of the base is provided withtwo peripheraligrooves 36 and 3.? arfl wranged to reg ster with the recesses 16 and The'screw-shell 25, secured ,uptnit e lower face of the; base',- and "the sectionsof. secured togetherv by two screws the -sections of the. base and in thefl'an e 28'.

position I laterally oifset portion 33 gyhich-lijesfwithin the recess'll' in the block upward as indicated in Fig, 2,-

:gfonned withan upwardly extending inclined passage of thecenter contact ems,

passages for the conducto the binding screws 15 and 22.. The adjacent I faces of theblocks '5 and 6 are provided with bosses 5. and .6 surrounding the holes througlrwhich the screws 26,- and 2h pass; and with lugsfi and fi wwhich serve'to, ac!

'curately maintain the opposing faces of the "blocks;

provides a strong base wk 11 parts described H h i for manufacture by shaping is well adapted switch platesff'rom the binding screwsto which the wires are attached. The switch block and contact plate, for making and breaking the circuit through the lamp are base while the binding screws 15-and 22 are located in the recesses. 16 which'are on the opposite side of the base where they are remote from the switchconjacts, and are also separated from the-switch. contacts and from eachother by intervening walls of porcelain. I

against relative movement either circuinferentially by duplicatesets of-latching devices arranged diametrically oppositei0 each other and adapted to be engaged by relative axial movement between the cap and shell. These latching devices each con- 'sistof a projection on one of the members of the basing provided with side and transrecess in the other member provided with cooperating locking shoulders.

fer to use is hown in Figs. l3 tolZ. As

formed in the wall of the shell and the co in the wall of the cap. As here shown, each.

of the shell on parallel axial lines at 139 and slitting the wall transversely at; 40b6- tween the axial slits 39. Theslitsf39fand 40 are so formed that they dohnot intersect.

project at right angles tofthe surface of the ing surface 41' extending toward the edge of the shell so'that the edge of the cap will readily slide over the tween the ends of the transverse and side slits the shell so that there is no danger of the off setor bent portion eifithe wall becoming displaced ,or of bending outwardlsuficiently the blocks at 'thefi' repel-f dlstance apart regardless of irregiiilanties in I p The. construction and arrangementfofthe?.

lccated inthevrecess 17 on one side'of the,

and 21 respectively verse locking shoulders,and an aperture or The formof latching device which I pie-- shell; Theprojection is formed with a slop V 21 respectivelyin the block 8, and to form r wires leading to dies, and. which; effectively insulates-the 9o Theshell 1 and ca- 2 forming the .inclosv 111g casing of the sec cat are locked togiether' axia y or shown in Fig 18 to 16, thieaprojections are operating recesses or apertures-are f0rmed projection 38 is formed by slitting the wall .116 The wall of the shell embraced within the slits is bentv or. forced outward to form abrupt shouldersatthe' slits 39 and 40,, which projection 1 as th p a is applied to the end of theshell. The inner a,

'ccr'ners 42 of the projection which lie be reniain integrally connected with the wall of a withthis relative'arrangement of the jectionfs and apertures as with the relative to a'llow-the wall of the ca to pass under theinner end'of the projectlon. \One of the projections 38is formed adjacentto the slot 43 in the shell through which thekey shaft I projects,.so'that the latching rejection may be forced radially inward in Y isengaging the cap' andshell. The: capis provided on diainetrieally oppositesides with two rectan gular-apert-ures' i adapted to receive the viththe side and transverseshoulders of the projections. 38; A positioning notch47 is .15

'for-n edfih the edgeofthe cap in line with each of the apertures 44, by slit-ting the wall of the cap axially in line with the axial ava'lls45- of the recesses, and bending the edge of the cap hetween'the axial slits outward slightly.

-Instead of forming the projections in the shell,' and theapertures in the cap, the'rela- -tive arrangement may be reversed. by forming the. apertures in the shell and the projections in the cap. Either arrangement may be employed, asmay be found more convenient or desirable inmanufacturing the eapsfand shells. In Figs. 17 and 18, a

different formand reverse arrangement of the projections and apertures is shown; As shown in these views, the projections 38- are formed in the'cap, the wall of the cap being} bent inward between the axial slits 39 andtwo transverse slits 40. The apertures 44' are formed in the wall of the shell.

'Positioning notches or depressions 47 are I formed in the 'edge of the shell'by bending inward the edge of the shell in line with the apertures 44. The manner of engaging anddlsengagmg the latching devices is the same pro- .arrangem'ent shown inv Figs. 13 to 16.- VVhen engaged, the side and transverse shoulders he look .the'pa'rts against relative movement in. either'directionQbOth circumferentially and axially, so that relative displacement of the partsunder comparatively heavy strains is so i In order to allow the inward'movemen't of the wall of the shell adjacent to the key slot 43, thefperiphery of the base block 5.- is re-' cessedfat 4.8 to receive the shell and insulat- "ingQlini'ng as the wall of the shell is bent inward. i j

"In order to prov1de an effective insulationbe tween the conductor cords and the socket cap in sockets which are adapted to 'b'e'su'spended by the conductor cords, a bush:

- 1. ing of insulating material is secured in the i opening in the top of the cap through which the oonductorcords pass. In; order to fac1h tat e the manufacture and introductlon of tl'1i;bushing into the aperture in the top of the cap, the bushing is provided with an annular shoulder adapted to engage the wall of the'ca) at "the edge of the aperture through w ich the bushing is inserted, and to retain the bushing in the aperture by 521111 engagement.

. Asshown in Figs. 1, 2, 13 and 14, a.

aperture at'the wall of the cap about the cord aperture through its top is slit as at with a .flange 51 adapted to underlie the wall ,of the cap, and to retain-the insulat in lining 4 in position in the cap. The bushmg is also provided with an annular rojection 52, which is of somewhat larger iameter than the aperture through the, cap, and theunder surface of which forms a shoulder 53 for engaging with the edge of the cap wall about the cord aperture, and thus retaining the bushing in position Within the aperture and with the fian'ge 51, clamping the insulating disk 4 against the wall of the cap. -The slitting of the wall of the cap about the cord aperture enables the bushing to be forced up through. the aperture until the annular project-ion 52'passes through the aperture,

- ing 54 is provided with a flange 55 arranged to underlie the wall of the cap, and to retain .the insulatin disk 4 within the cap. The

bushing is a so provided with'an annular groove 56'ar nged to lie just outside the w'all of the cap hen the bushing is in proper position in the aperture. The diameter of th ehbushing'above the groove 56 is substantiall aperture, so that the hashing may be readily passed through the' aperture from the inside of the cap. A ring 57 is introduced into the groove 56- after the bushing has been inserted in the aperture, and is of sucha diameter that it projects beyond the ed e of the aperture and the under; surface 0% the ring forms a shoulder for engaging the wall of the cap at the edge of the aperture and retaining the bushing in osi'tion. The ring 57 may be and preferab y is a'split spring ring, which may be readilya plied to the groovein the bushing, or may; e'readily re moved in casez -itli's desiredto remove "the bushing for the purpose of refinishing'the socket, orforanyiother purpose.

In Figs. 20'and21 a different form of insulating bushing 1 and securing means. is shown. As shown in these views, the bushing 58 is providedwith a {flange .59'adapted is) to "underlie haven: of. the cap, and to the same as the diameter of the &

tain the insulating disk 4 in position in the cap. Above the flange 59 the bushing is 61 for engaging the wall of the cap at the edge of the aperture, and retaining thebushing in position. This form of bushing may be introduced into the aperture by-bending the wall of the cap about the aperture inward as indicatedat 62, Fig. 21, and shearing through orslitting the wall of the cap about the edge of the aperture, as indicated at '63. ,..With the wall of the cap about the: aperture thus bentand grooved, the bushing may be introduced into the aperture from the inside of the cap, as indicated in Fig. 21,- and then the wall of the cap about the aperture bent upward, as indicated in Fig. 20,'thus bringing the edge of the aperture into the groove 60 and under the shoulder 61, so that the bushing is firmly held in the ,aperture in the cap.

While I prefer to embody the various features of the invention in a socket having the specific construction and arrangement of the parts shown and described, it will be understood that this specific construction and arrangement is not essential to the invention in its broader aspect, and may be varied and changed without departing from the invention. 1

Having explained the nature and objectof the invention, and specifically described some of the forms in which it may be em-i bodied, what I claim is p 1. A lamp socket, having,-in combination, an insulating base provided with an L- shaped positioning recess in its end, a center contact plate fitting within said recess and provided with a center contact finger 31 and a contact portion 33, a shell for receiving the lamp base secured to the end of the base and insulated from the plate, and a key- 'frame mounted. in the base and provided with a contact block coiiperating with the contact portion 33 of the plate, substantially as described. a .1 2,,A'lamp socket, hav ng in combination,

an insulating-base provided with a position- 1ng recess in its end, ashell' for receiving the lamp base, a plate in the recess provided with a spring portion, a center contact fingerprOjecting from the plate into the space Within the shell, and a switch block mountedin the base to coiiperate with the spring portion of the plate, substantially as described.

A lamp socket, having, in combination, an insulating base comprisin an upper block, arecess in the upper bloc for receivring. a key frame, a key .frame in the recess, a

key shaft in the frame provided at one end with a switchblock, a binding screw on 'the opposite end-of the frame, a lower block ceases covering therecess in the upper block, a peripheral recess in the lower block for the binding screw, a peripheral recess on theopposite side of thelower block for the switch block, a lamplbase receiving shellsecured oncured. between the shell and lower block having a portion overlying the switch block and a center contact finger projecting within the shell, and an insulating sheet between the latter plate described.

4, A lamp docket, having, in combination, an insulating base comprising an upper block, a recess in theupper block for receiving the key frame, a key frame in the recess, a key shaft in the frame provided at one end with a switch block, a lower block covering the recess in the upper block, a peripheral recess in the lower block for the switch block, a lamp base receiving shell secured on the lower face oi. the lower block, a plate secured between the shell; and block and pro vided with a portion underlying the switch block, and an insulating sheet between the plate and shell, substantially as described.

a shell and cap provided with aplurality of and the shell, substantially as 5. A lamp socket, having, incombination,

latching devices symmetrically arranged about the axis of the socket, and each conslsting of a projection on one part having ,two sides and a transverse locking shoulder,

and a recess in the other part having corre-.

sponding. shoulders and adapted to beengaged with the projection solely by relative axial movement between the cap and shell, substantially as described.

6. A lamp socket, .having, in combination,

a cap and shell one of said members bein provided with a recess, having two sides and a transverse locking shoulder, and the other member being provided with correspond ingly located side and transverse slits, and having the wall between the slits displaced .to form abrupt locking'shoulders whereby the cap and shell may be latched together by a relative axial movement ,and l'ocked against axial or circumferential movement, substantially as described.

-7. A lamp socket, having, in combination,

acap and shell one of said members being ,providedwith a recesshaving two sides and a transverse locking shoulder, and the other member being; rovided with correspondingly located si e and transverse slits, and having the wallbetweenthe slits displaced to form abrupt locking shoulders, and a positioning notch in the edgeaof the recessed member adapted to engage the projection on the other member, substantially as described 8. A lamp socket, having, in combination secting intermediate transverse slit, andv having the wall betweenthe slits displaced to form abrupt shoulders at the slits, and

the other member having a recess with corresponding abrupt side and transverse shoulders, substantially as described.

9. A lamp socket, having, in combination, a shell, a, cap rovided with a cord aperture in its top, and an insulatingbushing adapted to be projected through the aperture from within the cap and provided with a flange for underlying the Wall of the cap about the aperture, and with a shoulder for engaging the edge of the aperture and retaining the bushing "therein, substantially as described.

10. A lamp socket cap having a cordaperture in its'top, and an insulating bushing adapted to be projected through the aperture from within the on having a flan e for underlying the wall 0? the cap about t e aperture, and a'shoulder for engaging the edgeof the aperture and retainin the bush ing therein, substantially as described.

11. A lam-p socket, having, in combination, a cap and shell, one of said members being provided with two side slits and twonon-in tersecting transverse slits, and having the wall between the slits disposed to form four abrupt shoulders at the slits, and the other member having a recess forming a corresponding abrupt side and transverse shoulders, substantially as described.

'In testimon whereof I afiix my signature, in presence or two witnesses.

' NORMAN MARSHALL. Witnesses:

WARREN G. OGDEN, N. D. MGPI'IAIL. 

